docs: def feature_path(self, gff_path):
          """Load a GFF file with information on a single sequence and store features in the ``features`` attribute
  
          Args:
              gff_path: Path to GFF file.
  
          """
          if not gff_path:
              self.feature_dir = None
              self.feature_file = None
  
          else:
              if not op.exists(gff_path):
                  raise OSError('{}: file does not exist!'.format(gff_path))
  
              if not op.dirname(gff_path):
                  self.feature_dir = '.'
              else:
                  self.feature_dir = op.dirname(gff_path)
              self.feature_file = op.basename(gff_path)